becomes necessary to replace them by an artificial fall. Von Rathen and Ellis's Device In 1866 Anthony Bernhard Baron Von Rathen and George Henry Ellis, both of London, applied for and obtained British patent on "A New or Improved Mode of Constructing a Motive-power Wheel Whereby to Obtain Permanent Motion by the Application of Compressed Air or any other Elastic Fluid." In the specifications for patent the essentials of their invention are described as follows: This invention may be considered supplementary to an invention of the Baron Von Rathen of an elementary motive-power engine, for which a patent has been granted to him, No. 818, and dated March 23, 1865, and consisting in a newly-discovered plan for the construction of a motive-power wheel or engine, on the principle that the motor, consisting of compressed air or other elastic fluid, is maintained in permanent activity and without removal or renewal, and the useful resistance of the air in the chambers is on the surface of a fixed cylinder, the motion is regular and direct, the wheel rotating on its fixed central axis. The nature of our present invention consists principally in our providing, instead of that a motive-power wheel having its axis upon fixed bearings in an eccentric position and turning in an oscillating cylinder. The motor being brought through a hollow shaft, or any convenient channel, is introduced into one or more closed chambers formed upon the longest arm of the power wheel for the purpose of driving it round; by this means, according to the uniform pressure of the elastic fluid upon all surfaces, we obtain not only a continuous but an additional degree of driving power from the leverage given by the position of the wheel. There is, as shown in Fig. 1 of the accompanying drawing, a fixed arm or driving rod fixed upon the cylinder by which to impart motion to a crank, piston, or other apparatus. We propose to obtain the motor by pumps worked by or in connection with the power wheel, and having other suitable and necessary appliances for regulating, storing, transmitting, and manipulating the force supplied to or communicated by the power wheel, as have been described, to be applied with the plan for working the elementary motive-power engine hereinbefore referred to. Fig. 1 is a vertical section of the power wheel revolving inside and moving the oscillating cylinder.